[AC-2027] Update Flexible Collections logic to use organization property (#7445)

* Remove unused feature flag

* Replace feature flag ref with org flag

* Remove deprecated feature flag to discourage use

* Add check to org.canCreateNewCollections

* Adjust init logic of components to avoid race conditions

* Make canCreateNewCollections logic more explicit

* Resolve merge conflicts with vault changes

* Update comments

* Remove uses of old feature flag

* Remove last of old feature flag

* Clean up feature flag

* Fix linting

* Fix linting

libs/common/src/admin-console/models/domain/organization.ts

@@ -177,11 +177,15 @@ export class Organization {
   }
 
   get canCreateNewCollections() {
-    return (
-      !this.limitCollectionCreationDeletion ||
-      this.isManager ||
-      this.permissions.createNewCollections
-    );
+    if (this.flexibleCollections) {
+      return (
+        !this.limitCollectionCreationDeletion ||
+        this.isAdmin ||
+        this.permissions.createNewCollections
+      );
+    }
+
+    return this.isManager || this.permissions.createNewCollections;
   }
 
   get canEditAnyCollection() {